Southern Water also warned the considerable use of hydrants in the area had left some residents with poor pressure or temporary loss of their water supply.

Bitterne Manor Primary School on Quayside Road has also been closed.

A rest centre has been set up at the Ascension Centre in Thorold Road for 60 residents who have had to leave their homes.

The council confirmed a licence to store fireworks had been issued to Southern Firework Factory Ltd in September.

A spokesman said the storage conditions at the premises “complied with the relevant conditions”.

“At the time of the licence application the premises was purely commercial with no residential accommodation attached. As such the licence permitted 250kg (550lbs) net explosive content to be stored in a steel container secured against unauthorised access,” he said.

Image copyrightHampshire Fire and Rescue Service

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Disruption is likely to last until early afternoon, Hampshire Fire and Rescue said

Image copyrightTim Jackson

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Ten crews were called after the fire set off dozens of fireworks – leaving a plume of smoke above the area

Image copyrightHFRS

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Hampshire Fire and Rescue said the cause of the fire was not yet known